The invention relates to an optoelectronic component that is made from a semiconductor element containing at least one p-n junction and that has one rear contact on the semiconductor element and one front contact in a contact window located in a passivation layer, and to the use of this optoelectronic component.
Optoelectronic components are being used increasingly in various fields for a wide variety of applications. For example, luminescent diodes are used as indicator lights and displays and for the construction of line arrays and flat screens.
FIG. 1 is a diagram of a line array of luminescent diodes for use as a print head, as is known from the book "Light Emitting diodes, An Introduction", by K. Gillessen and W. Schairer, published by Prentice Hall International, 1987, on page 225, FIGS. 7-9. In this case the p-n junctions 2 forming the light-emitting diodes are provided in a semiconductor element 1 and extend to a surface covered with a passivation layer 3, at which surface the emitting surfaces of the light-emitting diodes are defined by the p-n junctions 2, and the contact windows 6 are located in the passivation layer 3 within these light-emitting surfaces. The rear contact 4 covers the entire rear area of the semiconductor 1, while the front contacts 5 are placed like a frame around each contact window 6 and each merge with a conducting path 7 on one side of the contact windows 6.
The contacting arrangement of the individual luminescent diodes according to this prior art has substantial drawbacks. On the one hand, a large proportion of the emitting surface 2 is covered by the contact 5, so that the mean light efficiency is relatively low. On the other hand, the emitted light power, the uniformity of the light power from all the luminescent diodes and the electrically contacted surface depends on exact adjustment of the contacts, whereas misalignments can lead to considerable irregularities.